When national law conflicts with EU law, national law should immediately be set aside by national Courts.
Amministrazione delle Finanze v Simmenthal SpA (1978) Case 106/77
Simmenthal, a company importing beef into Italy from France, was required to pay a tax at the border, which clearly contradicts the EC provisions on freedom of good at the time.
Preliminary question before the Court:
After acknowledging the incompatibility, the Italian Court referred the case to the ECJ to know if EU Law had to be applied directly of if it should wait for the traditional constitutional Court procedure to strike it down for incompatibility to higher norms?
The Court mentions in its Judgement that any EC provision “renders automatically inapplicable every conflicting provision of current national law”.
The effect of EU Law supremacy is immediate, there is no need to wait for national procedures to strike down the impugned law, and it is rendered automatically inapplicable.
Cases such as Mangold indicate the ECJ's propensity to develop homemade bypassing mechanisms. In that case, the court decided that 'general principles of law' might also impose substantive rights and responsibilities on people. The fact that the sole argument provided for such an original idea was the examples of Rodriguez Caballero, Simmenthal, and Solred is a significant flaw in the reasoning. Craig contends that vertical direct impact is at issue in all three instances, and that the first two examples have nothing to do with basic legal principles. However, the ratio of Mangold was upheld and broadened by the European Court of Justice (ECJ) in Kukuvedci. In that case, the ECJ said that even if the deadline for the directive has not passed, and "general principles," may still be identified as a basis for an action, and that this is true even if the directive itself has not been violated. The horizontal/vertical direct impact difference loses practically all of its validity as a result of the logic provided by Mangold, as well as this most recent development.